Effect of dietary supplementation of grape skin and seeds on liver fibrosis induced by dimethylnitrosamine in rats

Abstract

Grape is one of the most popular and widely cultivated fruits in the world. Although grape skin and seeds are waste product of the winery and grape juice industry, these wastes contain large amounts of phytochemicals such as flavonoids, phenolic acids, and anthocyanidins, which play an important role as chemopreventive and anticancer agents. We evaluated efficacies of grape skin and seeds on hepatic injury induced by dimethylnitrosamine (DMN) in rats. Treatment with DMN significantly increased levels of serum alanine transaminase, aspartate transaminase, alkaline phosphatase, and bilirubin. Diet supplementation with grape skin or seeds (10% daily for 4 weeks) prevented these elevations. The grape skin and seeds also restored serum albumin and total protein levels, and reduced the hepatic level of hydroxyproline and malondialdehyde. Furthermore, grape skin and seeds reduced DMN-induced collagen accumulation, as estimated by histological analysis of liver tissue stained with Sirius red. Grape skin and seeds also reduced hepatic stellate cell activation, as assessed by α-smooth muscle actin staining. In conclusion, grape skin and seeds exhibited in vivo hepatoprotective and antifibrogenic effects against DMN-induced liver injury, suggesting that grape skin and seeds may be useful in preventing the development of hepatic fibrosis.

Quercetin improves bone strength in experimental biliary cirrhosis

“…Antioxidants are known to inhibit the activation of hepatic stellate cells, which are the major cell type involved in liver fibrosis and damage. Our data agreed with preceding studies, which reported that administration of quercetin and some other flavonoids leads to reduction of total bilirubin and hepatic enzymes 26,27 . AST and ALT were increased in BDL and BDL + quercetin groups during the period of experiment, and the De Ritis ratio (AST/ALT), as an indicator of liver damage, did not differ between these two groups.…”

“…Our data agreed with preceding studies, which reported that administration of quercetin and some other flavonoids † ‡ ‡ leads to reduction of total bilirubin and hepatic enzymes. 26,27 AST and ALT were increased in BDL and BDL + quercetin groups during the period of experiment, and the De Ritis ratio (AST/ALT), as an indicator of liver damage, did not differ between these two groups. According to our knowledge, higher activities of ALT and AST are usually seen in extrahepatic cholestasis.…”

Effect of Grape Seed Extract, Gervital, Against Methotrexate Induced Histological and Ultrastructural Alterations in Testes of Albino Rats

“…All the above result depending on the scavenging activity of GSE that compete the free radicals-induced damage (result from MXT toxicity). Similarly, Shin and Moon (2010) indicated that GSE has antioxidant properties due to the presence of flavonoids, polyphenols, anthocyanin, pro-anthocyanidins, procyonidins and resveratrol. Several studies suggested that GSE has the ability to increase intracellular vitamin C level (free radical scavenge) and decrease capillary permeability and scavenge oxidant and free radicals (Li et al, 2001;Maier et al, 2009).…”

Salt overload in fructose-fed insulin-resistant rats decreases paraoxonase-1 activity

“…In our model, serum albumin and protein levels are reduced probably due to protein synthesis disruption in the liver as observed by Shinn and Moon [18]. The damaged hepatocytes are potent sources of reactive oxygen intermediates and oxidative stress is important in many types of liver injury.…”